title: Interferon-α-conditioned human monocytes combine a Th1-orienting attitude with the induction of autologous Th17 responses: role of IL-23 and IL-12.
abstract: IFN-α exerts multiple effects leading to immune protection against pathogens and cancer as well to autoimmune reactions by acting on monocytes and dendritic cells. We analyzed the versatility of human monocytes conditioned by IFN-α towards dendritic cell differentiation (IFN-DC) in shaping the autologous T-helper response. Priming of naïve CD4 T cells with autologous IFN-DC in the presence of either SEA or anti-CD3, resulted, in addition to a prominent expansion of CXCR3+ IFN-γ-producing CD4 Th1 cells, in the emergence of two distinct subsets of IL-17-producing CD4 T cells: i) a predominant Th17 population selectively producing IL-17 and expressing CCR6; ii) a minor Th1/Th17 population, producing both IL-17 and IFN-γ. After phagocytosis of apoptotic cells, IFN-DC induced Th17 cell expansion and IL-17 release. Notably, the use of neutralizing antibodies revealed that IL-23 was an essential cytokine in mediating Th17 cell development by IFN-DC. The demonstration of the IFN-DC-induced expansion of both Th1 and Th17 cell populations reveals the intrinsic plasticity of these DC in orienting the immune response and provides a mechanistic link between IFN-α and the onset of autoimmune phenomena, which have been correlated with both IL-17 production and exposure to IFN-α.
authors.affiliation: Department of Cell Biology and Neurosciences, Istituto Superiore di Sanità, Rome, Italy.
authors.forename: Stefano M
authors.initials: SM
authors.lastname: Santini
authors.forename: Caterina
authors.initials: C
authors.lastname: Lapenta
authors.forename: Simona
authors.initials: S
authors.lastname: Donati
authors.forename: Francesca
authors.initials: F
authors.lastname: Spadaro
authors.forename: Filippo
authors.initials: F
authors.lastname: Belardelli
authors.forename: Maria
authors.initials: M
authors.lastname: Ferrantini
mesh_terms: D015496:CD4-Positive T-Lymphocytes / Q000187:drug effects / Q000502:physiology; D002454:Cell Differentiation / Q000187:drug effects; D016764:Cell Polarity / Q000187:drug effects; D002478:Cells, Cultured; D017077:Culture Media, Conditioned / Q000494:pharmacology; D003713:Dendritic Cells / Q000187:drug effects / Q000378:metabolism / Q000502:physiology; D006801:Humans; D016898:Interferon-alpha / Q000494:pharmacology*; D018664:Interleukin-12 / Q000378:metabolism / Q000502:physiology*; D053759:Interleukin-23 / Q000378:metabolism / Q000502:physiology*; D008213:Lymphocyte Activation / Q000187:drug effects / Q000502:physiology; D008954:Models, Biological; D009000:Monocytes / Q000187:drug effects* / Q000378:metabolism / Q000502:physiology; D018417:Th1 Cells / Q000187:drug effects / Q000502:physiology*; D058504:Th17 Cells / Q000276:immunology* / Q000378:metabolism / Q000502:physiology / Q000637:transplantation
chemical_list: D017077:Culture Media, Conditioned; D016898:Interferon-alpha; D053759:Interleukin-23; D018664:Interleukin-12